Automatic watering device

• US 3,182,914 A
• Filed: 08/19/1963
• Issued: 05/11/1965
• Est. Priority Date: 08/19/1963
• Status: Expired due to Term

• Current Assignee: Richard D. Hosier
• Original Assignee: Richard D. Hosier
• Inventors: Hosier, Richard D.
• Application Number:
  US04/302,886
• Time in Patent Office: 631 Days
• US Class Current: 137/78.3
• CPC Class Codes: A01G 25/167 Control by humidity of the soil itself or of devices simulating soil or of the atmosphere; Soil humidity sensors
• CPC Class Codes: G05D 22/02 characterised by the use of electric means
• CPC Class Codes: Y10T 137/034 Controlled by conductivity of mixture
• CPC Class Codes: Y10T 137/189 Soil moisture sensing

Claims

1. IN AN AUTOMATIC WATERING SYSTEM:

A PAIR OF METALLIC MOISTURE SENSING PROBES ADAPTED FOR SENSING THE MOISTURE CONTENT OF SOIL, THE RESISTANCE BETWEEN THE PROBES BEING INDICATIVE OF THE MOISTURE CONTENT OF THE SOIL, A RESISTIVE BRIDGE CIRCUIT HAVING ONE LEG CONNECTED TO SAID PROBES AND FIRST AND SECOND PAIRS OF TERMINALS, CONTROL MEANS FOR SAID WATER SYSTEM ADAPTED TO BE RESPONSIVE TO THE COINCIDENCE OF TWO SIGNALS IN PREDETERMINED PHASE RELATIONSHIP FOR ACTIVATING THE WATERING SYSTEM, MEANS FOR APPLYING AN ALTERNATING CURRENT SIGNAL OF PREDETERMINED FREQUENCY TO SAID CONTROL MEANS AND TO SAID FIRST PAIR OF TERMINALS, MEANS ADAPTED TO APPLY A SECOND SIGNAL TO SAID CONTROL MEANS HAVING A PHASE RELATIONSHIP TO THE ALTERNATING CURRENT SIGNAL DETERMINED BY THE PHASE OF THE INPUT SIGNAL THERETO, A TRANSFORMER ADAPTED FOR COUPLING THE SIGNALS FORMED AT SAID SECOND PAIR OF TERMINALS TO THE LAST MENTIONED MEANS CAUSING SUCH MEANS TO APPLY A SIGNAL TO SAID CONTROL MEANS IN SAID PREDETERMINED PHASE RELATIONSHIP WITH THE ALTERNATING CURRENT SIGNAL AND THEREBY CAUSE THE CONTROL MEANS TO ACTIVATE THE WATERING SYSTEM WHEN THE MOISTURE IN THE SOIL IN BETWEEN THE PROBES IS DRY CAUSING A PREDETERMINED VALUE OF RESISTANCE BETWEEN THE PROBES.